Pinning
When a FBIK effector’s channel is pinned, it will not move or rotate when you pose other parts of your character’s body.
Specifies the amount of IK for the FBIK effector and controls how much your character’s joints want to reach their associated effector's translation. For example, a Reach Translation of 1 sets that the effector is completely controlled by IK and its joints will try to reach the effector's translation. A Reach Translation of 0 disables the effector’s IK (allowing you to then animate the underlying FK skeleton joints) and its joints ignore the effector's translation. The default Reach Translation values for your hip, hand, and foot FBIK effectors are: 1.0 Foot Translate, 1.0 Hips Translate, and 1.0 Hands Translate.
Specifies the amount of IK for the FBIK effector and controls how much your character’s joints want to reach their associated effector's rotation. For example, a Reach Rotation of 1 determines that the effector’s rotation is completely controlled by IK and a Reach Rotation of 0 disables the effector’s IK (allowing you to then animate the underlying FK skeleton joints) on its rotation channels. The default Reach Rotation values for your hip, hand, and foot FBIK effectors are: 1.0 Foot Rotate, 1.0 Hips Rotate, and 0.0 Hands Rotate.